//求返回字符串字节数
let a = 'a',
  b = '中',
  c = 'Hello World';
  d = 15;
let str = 'hello你好123';
//文件 -> Blob -> 二进制
//Blob 是什么
const byteSize = str => new Blob([str]).size
console.log(byteSize(a));
console.log(byteSize(b));
console.log(byteSize(c));
console.log(byteSize(d));
console.log(byteSize(str));
console.log(new Blob([str,c]));
